[Unsaturated fatty acids in the lipids of the spermatozoa of Ovis amon aries L. and Sus scrofa domestica L].

Spectrophotometric investigations were carried out with five unsaturated fatty acids found in the composition of spermatozoid lipids of animals belonging to four breeds of Ovis amon aries L. Parallel comparative analysis were made of the fatty acids in the lipids extracted from spermatozoa of Landrace swine of the Sus scrofa domestica L. species. Differences were established as to the percent content of fatty acids, having low points of freezing. It is believed that the criterion of cold resistance of the spermatozoid membrane lipids ranges within definite limits, depending on the maximum content of fatty acids with possibly lowest temperatures of freezing. The comparative investigations of both species of animals with regard to the percent ratio of spermatozoid fatty acids of low points of freezing have yielded results that speak in favour of the Ovis amon aries L. species. The different points of freezing below the level of the physiologically admissible temperature is referred to as one of the reasons for disturbances of the barrier functions of the membrane at deep freezing.